1. Field of the Disclosure
The present invention relates to water-based photocrosslinkable correction fluids.
Correction fluids, for correcting marks made by a writing implement, in particular a pen, are well known. Such fluids are applied to the mark present on a piece of paper and when they dry they provide a film, generally white in color, which covers the erroneous mark. A correction mark may then be applied to the dry film.
Two types of physically drying fluids (evaporation of solvents) are currently available on the market:                based on organic solvent: quick-drying but release VOCs.        water-based: non-toxic but slow-drying, generally with a drying time >120 s.        
Another existing corrector system is that of the roller, but in this case the formula is a dry formula, and although drying is very rapid and does not release VOCs, the technology is completely different.
2. Description of the Related Art
Patent application WO94/11450 describes a photocrosslinkable correction fluid having a short drying time of less than or equal to 10 s. However, either this fluid does not contain solvents, or it contains a volatile solvent, that is to say an organic solvent. Now, the use of a volatile solvent poses problems of releasing VOCs. In addition, a correction fluid without solvent poses a problem of migration of the writing ink after deposition (the writing mark reappears through the correction fluid) due to too shallow a crosslinking of the film because of the too high concentration of photocrosslinkable materials in this fluid.
Application US2012/0041092 describes an opaque coating composition comprising a resin which is able to crosslink to form a film under the action of UV radiation. This composition is therefore photocrosslinkable. However, this document does not describe a correction fluid. Indeed, the only usage examples relate to paints. Moreover, the composition described is not intended to be used on paper. It is also not intended to cover marks left by rollerball pen ink or ballpoint pen ink or a gel ink, without this ink reappearing (bleeding), without the composition being absorbed by the paper and while subsequently enabling re-writing on the dry film obtained. Indeed, the pigment content described and exemplified in this document is insufficient to have a good covering power over such marks and in particular for the film obtained after drying to avoid phenomena of gradual reappearance of the ink. In addition, in paragraph [0071], this document describes that the crosslinking energy is 100 MJ/cm2 to 5000 MJ/cm2, which is very high. It appears difficult to propose a writing product requiring such a crosslinking energy, due to the safety risks to the consumer. Moreover, using a lower energy would either be ineffective or would increase the drying and crosslinking time too much (several hours). Moreover, the compositions described in this document are not totally devoid of organic solvents.
Application EP2557094 also describes a water-based coating composition which is crosslinkable by radiation. For the same reasons as above, such a composition could not be used as a correction fluid, since the pigment content described and exemplified in this document is insufficient to have a good covering power over the marks left by the rollerball pen ink or ballpoint pen ink or by a gel ink, and in particular for the film obtained after drying to avoid phenomena of gradual reappearance of the ink.
Application EP 2703459 describes a photocrosslinkable ink. It is therefore not a correction fluid and the pigment content described and exemplified in this document is insufficient to have a good covering power over the marks left by the rollerball pen ink or ballpoint pen ink or by a gel ink, and in particular for the film obtained after drying to avoid phenomena of gradual reappearance of the ink.
In addition, according to this document, it is possible that the compositions proposed may contain organic solvents of glycol, glycol ether and alcohol type. This type of solvent may either modify the appearance of the writing mark to be covered (diffusion of the ink into the paper) or cause the problem of bleeding (migration of the writing mark through the correction fluid film).
Thus, none of the documents of the prior art describes or suggests that it is possible to obtain a water-based correction fluid which dries rapidly, that is to say having a drying time of between 5 and 30 seconds.